Improvements in space-time accessibility as outcomes of heavy rail transit development in the sprawled residential district. Empirical evidence from Gdansk

The sustainable mobility paradigm is essential to cities' climate mitigation. Transit-oriented development (TOD) supporting the concentration of housing, workplaces, facilities, and services within a walkable distance of transport nodes connected by efficient public transport results in the use of sustainable mobility implementation. Despite the growing scientific interest in TOD, the legal, economic, cultural, and physical obstacles complicate and slow down its implementation process. This article provides new insight into the outcomes of planned heavy rail transit (HRT) development across the sprawled residential district, which emerged due to market-driven housing development, intense individual motorisation, and permissive spatial policy that enables extensive housing without relevant transit investments. Based on quantitative data regarding spatialities of the case study area, space-time accessibility was the primary research method. Despite the unfavourable local context to mass transit, the investigation reveals significant planned HRT line spatial-time accessibility attempts. The most significant is the by-transit travel time reduction and an increase in to-transit accessibility. Due to urban sprawl outcomes, the HRT line requires an extensive feeder system. It increases operational costs and risks the reliability of the whole trunk-and-feeder system due to possible feeder operation disturbance resulting from road congestion. The study outcomes yield significant implications for urban transport policy.